I've never understood how this works from the tutorial as far as syntax. Basically all I want is a message that says "You currently have " +PointsGlobal.GetValue() as int+ " points left to spend."
What do I actually type into the message box?

Three ways:

Debug.Messagebox("You currently have " + PointsGlobal.GetValue() as int + " points left to spend.") <<<< displays an actual messagebox
Debug.Notification("You currently have " + PointsGlobal.GetValue() as int + " points left to spend.") <<<< displays a message in the upper left. Note that the font size decreases as you add characters. I think somewhere around 15-16 is the max for normal size.
MyMessage.Show(PointsGlobal.GetValue() as int)

MyMessage is a property for a message form you've created.
The text in the message form would be: You currently have %f points left to spend.
http://www.creationkit.com/Show_-_Message

The formatting works only with numbers.

How do I make a "property for a message form"?